Ohm’s Law Calculator
⚡ Electricity & magnetism. Use the Ohm’s law formula to find voltage, current, resistance: pick the value you want, type the others, and the answer updates as you go.
Voltage6 V
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Voltage | V |
| Current | A |
| Resistance | Ω |
Worked example
Find the voltage when Current = 0.5 A, Resistance = 12 Ω.
Using V = IR: Voltage = 6 V.
Frequently asked questions
What is the formula for Ohm’s law?
V = IR.
What do the letters stand for, and what units are used?
Voltage in V, Current in A, Resistance in Ω.
How do you calculate voltage?
Put the values into V = IR. For example, with Current = 0.5 A, Resistance = 12 Ω, voltage = 6 V.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (voltage, current, resistance) and fill in the others: it rearranges the formula for you.
